1. Field of the Invention
The present invention relates to a stop device provided in a zoom lens.
2. Description of the Related Art
Conventionally, an aperture-stop of a zoom lens is provided close to and in front of a rear lens group, and is connected to the rear lens group as a single body, as disclosed, for example, in Japanese Unexamined Patent Publication No. 58-62632. Namely, in a zooming operation, the aperture-stop is moved together with the rear lens group, and the distance between the aperture-stop and the rear lens group is set to as small a gap as possible, to ensure that the aperture-stop does not interfere with a front lens group when moved toward the front lens group.
On the other hand, a known power zoom lens is constructed in such manner that a front lens group and a rear lens group are moved by a motor housed in a rear portion of a lens barrel. In this power zoom lens, however, because the rear lens group can be moved to a position close to a rear end of the lens barrel in a zooming operation, the aperture-stop would interfere with the motor if the aperture-stop was provided immediately in front of the rear lens group.